Vitamin B12 is claimed to promote rapid inflammation associated with the eruption of pimples. A new study has put into perspective the vitamin’s effect on facial bacteria that seem to account for acne formation. The findings have been published in Science Translational Medicine.

Vitamin B12 is found in meat and dairy products. It is also commonly taken as supplement, believed to boost brain activity, and fighting aneamia. A new study has, however, revealed the downsides of having the vitamin in extra amounts. It seems that the vitamin modifies the genetics of bacteria found on the face, leading to rapid inflammation thereby causing pimples. The cause of acne itself is not clearly established among researchers.

Therefore, Huiying Li, a molecular pharmacologist at the University of California-Los Angeles, together with her team, set out to determine whether high levels of B12 can lead to the formation of acne.

“It has been reported several times that people who take B12 develop acne,” she said in statement to The Verge.

They first identified the molecular pathway that generates vitamin B12 in the skin bacterium known as Propionibacterium acnes. This was then compared in people with good skin and those with acne. The results showed that the pathway in P. acnes was considerably down-regulated in people with acne as opposed to those with healthy skin.

Thereafter, the researchers analysed the effect of increased B12 consumption from external sources on the concentrations of naturally-produced B12 in the skin bacteria. Volunteers with healthy skin signed up for this part of the experiment and they were given vitamin B12 injections. They found that the supplement repressed the expression of genes in P. acnes that synthesise B12. This effect was similar to those of acne patients. One of the volunteers who initially had clear skin developed acne in one week.

They concluded that the extra intake of B12 could be promoting the skin bacteria to decrease their production of it, which then creates a situation conducive for the development of acne.

“It’s exciting that we found that the potential link between B12 and acne is through the skin bacteria,” Li said in a statement.